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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
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 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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import java.util.ArrayList;
import java.util.Collections;
import java.util.ConcurrentModificationException;
import java.util.List;

/**
 * @test
 * @bug 8340572
 * @summary ConcurrentModificationException when sorting ArrayList sublists
 */

public class SortingModCount {
    public static void main(String[] args) {
        testSortingSubListsDoesNotIncrementModCount();
        testSortingListDoesIncrementModCount();
    }

    private static void testSortingSubListsDoesNotIncrementModCount() {
        List<Integer> l = new ArrayList<>(List.of(1, 2, 3, 4));
        var a = l.subList(0, 2);
        var b = l.subList(2, 4);
        Collections.sort(a);
        Collections.sort(b);
    }

    private static void testSortingListDoesIncrementModCount() {
        List<Integer> l = new ArrayList<>(List.of(1, 2, 3, 4));
        var b = l.subList(2, 4);
        Collections.sort(l);
        try {
            Collections.sort(b);
            throw new Error("expected ConcurrentModificationException not thrown");
        } catch (ConcurrentModificationException expected) {
        }
    }
}
